#include <cstdio>
#include <iostream>
#include <unistd.h>
#include <cstring>

int main()
{
    printf("hello print\n");
    fprintf(stdout,"hello fprintf\n");

    const char* msg="hello fwrite\n";
    fwrite(msg,strlen(msg),1,stdout);

    const char* s="hello write\n";

    write(1,s,strlen(s));

    fork();

    return 0;
}
